CMV retinitis is the most common intraocular infection in patients with AIDS. Over time, untreated CMV retinitis will destroy the retina. Prompt treatment of CMV retinitis involving the posterior pole is required to limit vision loss and blindness. Two drugs have been licensed by the FDA for treatment of CMV retinitis. Unfortunately, progression ultimately ensues despite use of either agent. HPMPC is a nucleotide analog with potent activity against a broad spectrum of herpes virus, including those which cause disease in humans.